Strategies for meeting the N requirement of modern wheat varieties for both yield and protein with new fertilizers and fertilizer additives J Ransom, C. Feland, M. Rellaford and N. Schimek
Background Nitrogen is the most important fertililzer input in terms of quantity and cost in wheat production Amount of N applied can impact both yield and protein Many newer varieties may benefit from more intensive N management Nitrogen is subject to loss which can impact crop performance and environmental quality
Background Report of the 2016 results of a series of experiments funded (partially or completely) by Minnesota Wheat Checkoff funds These experiments seek to answer questions around the efficiency and profitability of nitrogen fertilizer management I will summarize data that will be presented in more detail by the students conducting this research this afternoon
Can fertilizer use efficiency be improved with fertilizer type, timing or the addition of a stabilizer? Treatments include Urea ESN a polymer coated urea that has slow release properties Instinct newer formulation of nitrapyrin (N-Serve) recently registered for use on wheat that is more adaptable for use with urea UAN streamed in a split scenario with or without Agrotain Fall verses spring application
100.0 Comparison of urea and ESN at three rates, 2016 90.0 80.0 70.0 Yield (bu/ac) 60.0 50.0 40.0 30.0 ESN Urea 20.0 10.0 0.0 50 75 100 Untreated N-Rich Rate Optimum N (%)
14.5 Effect of N Type and Rate on Protein, 2016 14.0 13.5 Protein (%) 13.0 12.5 12.0 11.5 11.0 ESN Urea 10.5 10.0 50 75 100 Untreated N-Rich Rate Optimum N (%)
100 Effect if N Type and Timing on Yield, 2016 (100% Rate) 95 90 Yield (bu/ac) 85 80 75 70 ESN Urea 50 50 75 25 Instinct UAN 65 60 Fall Timing of Application Spring
13.8 Effect of N Type and Timing on Protein, 2016 (100% Rate) 13.6 Protein (%) 13.4 13.2 13.0 12.8 ESN Urea 50 50 75 25 Instinct UAN 12.6 Fall Timing of Application Spring
76 Effect of N Type and Timing at 100% Rate on Yield, 2015 74 72 Yield (bu/ac) 70 68 66 ESN Urea 50 50 75 25 Instinct 64 62 Fall Timing of Application Spring
14.6 Effect of N Type and Timing at 100% Rate on Protein, 2015 14.4 Protein (%) 14.2 14 13.8 13.6 ESN Urea 50 50 75 25 Instinct 13.4 13.2 Fall Timing of Application Spring
Conclusions N additions gave marginal responses in yield due to extremely good conditions for mineralization, 2016. Generally, slightly better yields and protein from spring applications than from those in the fall ESN fairly consistently produced more protein than urea, but not yield Differences were in the 0.2 to 0.4 percent range and might be economical only if protein premium/discount high Instinct was more variable in both yield and protein responses, but more often positive with spring applications In environments where N losses are minimal, the cheapest form of nitrogen will be the most profitable to use
If in-season N fertilizer applications can be used to improve efficiency and or as a rescue treatment when early season N losses are significant, when is the best timing and does N source matter? Treatments include 70% of recommended rate (in order to seed a response and to mimic a situation when a rescue treatment is needed) used a basal rate Timings: 4-5 lf stage, boot, and post-anthesis Source: urea, UAN, UAN plus water
Effect of nitrogen timing and amount on protein at two locations, 2016 Treatment ADA Yield (bu/a) RLF Check 47.6 62.5 70% rate urea at planting (77 lbs/acre) 60.3 69.7 100% rate urea at planting (110 lbs/acre) 69.7 74.7 70% rate urea at planting (77 lbs/acre) + 30 lbs N as urea 4 to 5 leaf stage 70.3 75.0 70% rate urea at planting (77 lbs/acre) + 30 lbs N as UAN 4 to 5 leaf stage 72.2 73.1 70% rate urea at planting (77 lbs/acre) + 30 lbs N as urea at the boot stage 69.7 73.2 70% rate urea at planting (77 lbs/acre) + 30 lbs N as UAN at the boot stage 71.9 74.4 70% rate urea at planting (77 lbs/acre) + 30 lbs N of UAN at flowering 70.6 72.5 200 lbs. urea at planting 67.0 74.5 LSD 7.0 6.1
Effect of nitrogen timing and amount on protein at two locations, 2016 Treatment ADA percent protein RLF Check 11.4 11.0 70% rate urea at planting (77 lbs/acre) 12.1 12.5 100% rate urea at planting (110 lbs/acre) 12.7 13.1 70% rate urea at planting (77 lbs/acre) + 30 lbs N as urea 4 to 5 leaf stage 12.9 13.4 70% rate urea at planting (77 lbs/acre) + 30 lbs N as UAN 4 to 5 leaf stage 12.9 12.4 70% rate urea at planting (77 lbs/acre) + 30 lbs N as urea at the boot stage 13.2 13.5 70% rate urea at planting (77 lbs/acre) + 30 lbs N as UAN at the boot stage 12.6 13.0 70% rate urea at planting (77 lbs/acre) + 30 lbs N of UAN at flowering 13.2 13.3 200 lbs. urea at planting 13.0 13.6 LSD 0.0 0.4
Conclusions Little discernable differences in N timing on yield lots of mineralization and minimal losses In-season applications tended to be slightly more effective than all at planting for increasing protein concentrations With urea, boot applications tended to be slightly better than at 4 lf stage for increasing protein Post anthesis foliar applications did not produce the most protein of the in-season treatments as we observed in previous season Urea performed consistently better than UAN
Can we predict the yield of a crop early enough to guide a decision on the profitability of in-season N applications? Sensors Crop Simulation models
Relationship between NDVI at boot stage and grain protein at harvest, RLF, 2016 15.00 14.00 Grain Protein % 13.00 12.00 11.00 10.00 y = 22.017x - 5.9101 R² = 0.3625 9.00 8.00 0.78 0.8 0.82 0.84 0.86 0.88 0.9 0.92 NDVI at Boot Stage
Can we improve the efficacy of a late season foliar N application or combine it with our fungicide applications Experiment 1: Can UAN or urea solution be applied with a fungicide used for scab control? Experiment 2: Does droplet size and or surfactant type impact protein enhancement? Table 1. Experiment one individual treatment and N timing. Nitrogen rate of 33 kg ha -1 and volume applied 187 L ha -1. Treatment Timing 1.) No treatment 2.) Fungicide + NIS Zadoks 65 3.) Fungicide + NIS UAN application 4.) Fungicide + NIS Urea Solution application Zadoks 65 Zadoks 69 Zadoks 65 Zadoks 69 5.) Fungicide + NIS + UAN Zadoks 65 6.) Fungicide + NIS + Urea solution Zadoks 65 7.) UAN Zadoks 65 8.) Urea solution Zadoks 65 9.) UAN Zadoks 69 10.) Urea solution Zadoks 69 11.) UAN + Urease inhibitor Zadoks 65 12.) Urea solution + Urease inhibitor Zadoks 65 NIS = Non-Ionic Surfactant UAN= Urea Ammonium Nitrate (28-0-0)
Preliminary Results: Exp. One 10.0 9.0 8.0 Percent Leaf Burning (1-9): Experiment One LSD: 1.2 Visual Scale (1-9) 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 1.) Control: No treatment 2.) Prosaro + NIS 3.) Prosaro + NIS, UAN 5 Days Post Anthesis 4.) Prosaro + NIS, Urea Solution 5 Days Post Anthesis 5.) Prosaro + NIS + UAN 6.) Prosaro + NIS + Urea solution 7.) UAN solitarily at anthesis 8.) Urea solution solitarily at anthesis 9.) UAN solitarily 5 days post anthesis 10.) Urea solution solitarily 5 days post anthesis
Treatment 1: Check Treatment 5: Prosaro + NIS + UAN
Preliminary Results: Exp. One 14.60 14.40 Grain Protein LSD: 0.34 14.20 Grain Protein (g/kg) 14.00 13.80 13.60 13.40 13.20 1.) Control: No treatment 2.) Prosaro + NIS 3.) Prosaro + NIS, UAN 5 Days Post Anthesis 4.) Prosaro + NIS, Urea Solution 5 Days Post Anthesis 5.) Prosaro + NIS + UAN 6.) Prosaro + NIS + Urea solution 7.) UAN solitarily 8.) Urea solution solitarily 9.) UAN solitarily 10.) Urea solution solitarily
Table 3. Experiment two individual treatment components. Nitrogen solution treatment Adjuvant Nozzle Spray volume ratio Rate 1.) No treatment 2.) UAN 1 1:1 3.) UAN 2 1:1 4.) UAN MSO 1 1:1 1.75 l ha -1 5.) UAN MSO 2 1:1 1.75 l ha -1 6.) UAN POC 1 1:1 2.34 l ha -1 7.) UAN POC 2 1:1 2.34 l ha -1 8.) UAN NIS 1 1:1 0.5% v/v 9.) UAN NIS 2 1:1 0.5% v/v 10.) UAN MSO & OS# 1 1:1 438 ml ha -1 11.) UAN MSO & OS 2 1:1 438 ml ha -1 12.) UAN Urease Inhibitor 1 1:1 2.34 l ha -1 13.) Urea solution Urease Inhibitor 1 1:1 4.68 l ha -1 14.) UAN 1 1.5:1 15.) UAN 1 3:1 Ratio of nitrogen solution to water volume MSO = Methylated Seed Oil POC = Petroleum Oil Concentrate NIS = Non-Ionic Surfactant # MSO & OS = Methylated Seed Oil & Organosilicone Surfactant XR11002 TT1102
Preliminary Results: Exp. Two 13.80 Grain Protein: Adjuvant and Droplet Size 13.60 Grain Protein (g kg-1) 13.40 13.20 13.00 12.80 12.60 1.) Check 2.) UAN Medium Droplet 3.) UAN Coarse Droplet 4.) UAN + MSO Medium Droplet 5.) UAN + MSO Coarse Droplet 6.) UAN + POC Medium Droplet 7.) UAN + POC Coarse Droplet 8.) UAN + NIS Medium Droplet 9.) UAN + NIS Coarse Droplet 10.) UAN + MSOOS Medium Droplet 11.) UAN+ MSOOS Coarse Droplet
Conclusions Less damage at flowering than previously thought UAN more burn than urea solution but less effective? Five days post flowering, better than flowering Surfactants did not enhance protein content Droplet size, coarse better than medium with surfactant, otherwise medium better than coarse